KR20070120037A - Toner for developing electrostatic image and image formation process using it - Google Patents

Abstract

A toner for developing an electrostatic image is provided to contain a charge control agent that causes a fast rise rate of electrification, has excellent electrification characteristics, and forms a vivid image with high resolution. A toner for developing an electrostatic image includes: a charge control agent comprising an azo-based iron complex salt which is represented by the following formula (1) and has an average particle size of 1-4 micron and a specific volume resistivity of 0.2x10^15 to 7x10^15 ohm cm; and a binder resin for a toner. In the formula 1, R^1 and R^3 are identical to or different from each other and are straight or branched C3-8 alkyl groups, R^2a, R^2b, R^4a, and R^4b are identical to or different from one another and are selected from the group consisting of a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a nitro group, and a carboxy group, and A^+ represents m(H^+) + n(K^+) + p(Na^+)(wherein, m, n, and p are numbers capable of satisfying the following conditions of m+n+p=1, 0.7<=m<=1, 0<=n<=0.3, 0<=p<=0.3).

Description

Toner for electrostatic charge image development and image formation method using the same {TONER FOR DEVELOPING ELECTROSTATIC IMAGE AND IMAGE FORMATION PROCESS USING IT}

1 is a schematic diagram of an apparatus for measuring the volume specific resistivity of a charge control agent made of an azo-based iron salt to which the present invention is applied;

2 is a synchronous distribution diagram when the electrostatic image developing toner of Example 1 to which the present invention is applied is measured by a particle analyzer;

Fig. 3 is a synchronous distribution chart when the electrostatic charge image developing toner of Example 4 to which the present invention is applied is measured by a particle analyzer;

4 is a synchronous distribution diagram when the electrostatic charge image developing toner of Comparative Example 3 outside the scope of the present invention is measured by a particle analyzer.

<Description of the symbols for the main parts of the drawings>

1: lower electrode

2: upper electrode

3: ring

5: ammeter

6: measure the sample

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for electrostatic image development containing a negative or negatively charged charge control agent containing azo iron salts used in toners and powder coatings.

Electrophotographic methods are used in copiers, printers, and facsimiles. In this system, an electrostatic latent image is developed by toner tribocharged on a photosensitive member having a photosensitive layer containing an inorganic or organic light conductive material, transferred to a recording paper, and fixed.

To increase the charging speed of the toner, or to sufficiently charge the toner to stabilize and control the amount of charge appropriately, to increase the charging characteristics, or to develop the image at a high speed by controlling the electrostatic latent image stably, In order to form a clear image of the ink, a charge control agent for appropriately controlling the charging is added to the toner in advance.

As such a charge control agent, for example, an incident metal complex salt is disclosed by Unexamined-Japanese-Patent No. 61-101558, Unexamined-Japanese-Patent No. 61-155463, and Unexamined-Japanese-Patent No. 62-177561. have.

With recent advances in high performance, such as improved resolution of copiers and printers, and high-speed developments in electrophotographic methods, as well as the expansion of applications such as low-speed developments, the charging of toners is further accelerated, resulting in more excellent charging characteristics and higher resolution. There has been a demand for a charge control agent capable of forming a clear image of the ink, and a toner using the same, which can be produced easily and with good yield. In addition, there has been a demand for a charge control agent that can be used for powder coatings used for electrostatic powder coating, which attracts and calcines electrostatically charged powder coatings to the charges on the surface of the structure.

Disclosure of the Invention

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to quickly raise the charging, to develop excellent charging characteristics, to form a high-resolution clear image, and to maintain the charging with stability over time, and environmental stability An object of the present invention is to provide a toner for developing electrostatic images containing an excellent charge control agent.

The present inventors have found that toner having excellent chargeability can be obtained by appropriately adjusting the average particle diameter and volume specific resistivity of a specific azo-based iron salt contained in the charge control agent, and completed the present invention.

The electrostatic charge image developing toner of the first aspect of the present invention made to achieve the above object is represented by the following general formula (1), and has an average particle diameter of 1 to 4 µm and a volume specific resistivity of 0.2 to 10 ¹⁵ to. A charge control agent containing an azo-based iron salt of 7 × 10 ¹⁵ Ω · cm and a binder resin for toner are included:

In the formula (1), R ¹ and R ³ are the same as or different from each other, and are a linear or branched alkyl group having 3 to 8 carbon atoms; R ^2a , R ^2b , R ^4a and R ^4b are the same or different from each other and are selected from the group consisting of a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a nitro group and a carboxyl group; A ⁺ represents m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ), wherein m, n and p are m + n + p = 1, 0.7 ≦ m ≦ 1, 0 ≦ n ≦ 0.3 And 0 ≦ p ≦ 0.3. However, m, m and p of m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ) are the abundance ratios (count molar ratios) of counter ions (cations) in the azo-based iron salt of formula (1), respectively. ).

The electrostatic charge image developing toner according to the second aspect of the present invention is characterized in that, in the first aspect, the weight loss rate of the azo-based iron salt by differential thermal thermogravimetric analysis is 90% or more.

The electrostatic charge image developing toner according to the third aspect of the present invention is characterized in that the first aspect further comprises wax.

The toner for electrostatic charge image development according to the fourth aspect of the present invention is the glass in which the center metal Fe of the glass azo-based iron salt is measured as the ratio of glass liberated from the toner of the azo-based iron salt in the first aspect. The rate is in the range of 0.01 to 3%.

The electrostatic charge image developing toner according to the fifth aspect of the present invention is characterized in that, in the first aspect, the charge amount at a high temperature of 35 ° C and a high humidity of 90% relative to the charge amount at 25 ° C and a relative humidity of 50%. The reduction rate is characterized in that 0.1 to 10%.

The electrostatic charge image developing toner according to the sixth aspect of the present invention is characterized in that in the first aspect, 0.1 to 10 parts by weight of the charge control agent and 100 parts by weight of the toner binder resin are included.

The image forming method according to the seventh aspect of the present invention includes the electrostatic image developing toner according to any one of the first to sixth aspects, on a developer carrier disposed to face the electrostatic latent image bearing at intervals. Adsorbing the developer to form a toner layer; And adsorbing the toner in the toner layer to the electrostatic latent image bearing member to develop the electrostatic latent image.

The charge control agent used in the electrostatic charge image developing toner of the present invention is excellent in negatively charged women and stability thereof, and also has good dispersibility in the resin for toner. The electrostatic charge image developing toner of the present invention containing this charge control agent has a rapid rise, excellent stability over time of charging, and excellent storage stability and durability. In particular, since there are few impurities, safety is high and environmental stability is excellent.

According to the image forming method of the present invention using this toner, fixing and non-offset properties in a wide range of temperatures can be realized, and stable copy images can be formed.

Implement the invention  Form for

Hereinafter, although the Example of this invention is described in detail, the scope of the present invention is not limited to these Examples.

According to the studies of the present inventors, it has been found that when an image is formed from a toner containing a charge control agent, the particle size and resistance characteristics of the charge control agent greatly influence the developability and transferability.

The charge control agent used in the present invention is composed of the azo-based iron salt represented by the formula (1). This charge control agent has an A ^{+ value} of 0.7 ≤ m ≤ 1, 0 ≤ n ≤ 0.3, and 0 ≤ p represented by the counter ions m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ) of the azo iron complex salt. It is the range of ≤ 0.3. It is preferable that this volume specific resistivity is 0.2 × 10 ¹⁵ to 7 × 10 ¹⁵ Ω · cm. The higher the H ⁺ content of the charge control agent and the higher its constant volume specific resistivity, the higher the anti-war controllability.

The manufacturing method of the charge control agent containing the azo-based iron complex salt is a first step of obtaining a monoazo compound by a diazotization coupling reaction, a second step of ironizing the monoazo compound with an iron-complexing agent, A third step of preparing a counter ion, washing and purifying to obtain an azo-based iron salt represented by the above formula (1), and filtering and drying the azo-based iron salt as necessary.

In the above process, it is important to remove impurities generated, particularly impurities related to metals other than iron (Fe) contained in the ironing agent. For example, when impurities related to the metal of Mn contained in the ironing agent (the hydroxide of the metal is estimated) are mixed in the charge control agent, a decrease in the charge controllability becomes a problem. Specifically, about 3000 ppm of Mn was measured in the general industrial grade iron sulfate, which can be used as the ironing agent.

Optimized dissolution process of monoazo compound in the second step of ironing monoazo compound, improvement of ironing reaction efficiency, and preparation of azo iron complex salt under acidic conditions, precipitation, filtration, washing and purification, suitable volume inherent Azo iron salts having resistivity can be obtained.

A toner containing a charge control agent composed of azo-based iron salts causes leakage of the generated electric charges when the volume specific resistivity is less than this range, and when the volume specific resistivity is larger than this range, the generated charges become excessively stiff and stable. This lacks. Further, the volume specific resistivity is more preferably 0.5 × 10 ¹⁵ to 5.0 × 10 ¹⁵ Ω · cm.

A toner containing a charge control agent made of an azo-based iron salt having such a volume specific resistivity is sufficiently charged and exhibits excellent charge rise and stability over time.

In addition, a volume specific resistance is measured based on JIS standard (K6911).

The higher the H ⁺ content in the counter ion A ⁺ of the azo-based iron salt, the lower the hydrophilic salt structure of the charge control agent, resulting in less saturation and other environmental influences. Has good performance. In addition, due to the structure and the reduction treatment of impurities, the weight loss ratio by differential thermal thermogravimetric analysis shows physical properties of 90% or more. When the weight loss rate is 90% or more, the saturated charge and environmental stability of the toner containing the charge control agent are improved.

In addition, the average particle diameter of the azo-based iron salt as a charge control agent is ironized in water or in a water-organic solvent mixed solution, preferably in a monovalent lower alcohol-water mixed solution, and the particle size is adjusted while producing counter ions. It is preferable to set it as 1-4 micrometers. By properly adjusting the diameter of the particles of the charge control agent, the charge control agent can be dispersed well in the toner, whereby toner particles stably charged can be obtained. If the average particle diameter of the azo-based iron salt is larger than this range, the azo-based iron salt is easily peeled and separated from the toner in which the azo-based iron salt is dispersed.

The charge control agent used in the present invention has an average particle diameter of 1 to 4 µm and a volume specific resistivity of 0.2 × 10 ¹⁵ to 7.0 × 10 ¹⁵ Ω · cm, in particular 0.5 × 10 ¹⁵ to 5.0 × 10 ¹⁵ Ω · cm It is preferable that it consists of the azo-type iron complex salt of the said General formula (1). Since the toner for electrostatic image development containing the above has characteristics excellent in the above-described performance, physical properties, and the like, it is possible to quickly raise the charge, stably express excellent charge characteristics, and form a high-resolution clear image.

When the alkyl group in the azo-based iron complex salt of formula (1) has a long carbon chain, the hydrophobicity is improved, and as a result, it has a high saturation charging property and excellent environmental stability. A toner for electrostatic image development containing a charge control agent wherein R ¹ or R ³ is a butyl group, especially a tert-butyl group, exhibits better chargeability.

In general, toners containing azo iron complex salts as charge control agents exhibit relatively high amounts of triboelectric charges, but the amount of adsorbed water to the metal compound increases under high humidity, so that the charge amount decreases and low humidity is observed. Since the number of adsorbed water in the metal compound decreases under the following conditions, the resistance is increased, so that the charge rate is often lowered. However, the toner containing the azo-based iron salt of formula (1) as the charge control agent has a good combination of the skeleton structure of the azo-based iron ion and the counter ion, and thus exhibits excellent environmental stability against humidity.

The manufacturing method of the charge control agent containing the said azo-type iron complex salt is demonstrated further more concretely.

In the first step of carrying out the diazotization coupling, it is preferable to obtain a monoazo compound by carrying out the diazotization coupling reaction of a conventional method in water or a water-organic solvent mixed solution, preferably in a monovalent lower alcohol-water mixed solution. Do.

In the second step of ironing, the monoazo compound obtained in the first step is ferric sulfate, ferrous sulfate, ferric chloride, chloride in water or in a water-organic solvent mixture solution, preferably in a monovalent lower alcohol-water mixture solution. It is preferable to perform an ironing reaction with the ironizing agent illustrated by ferrous iron and ferric nitrate.

An important point in this production method is to adjust the amount of counter ions present in the azo iron complex salt as a product to a desired amount. Therefore, it is necessary to first measure the amount of alkali metal (eg, sodium) in the reaction solution and monoazo compound obtained by, for example, diazocoupling reaction using sodium nitrite in the diazocoupling step.

The amount of alkali metal remaining in the monoazo compound is subtracted to adjust the alkali, for example, sodium hydroxide, potassium hydroxide, and the like, and the alkali is added to the butanol-water mixture in which the monoazo compound is dispersed in the azo-based ironing step. By adding an ironing agent to the ironization reaction, an azo iron complex salt having a desired counter ion abundance ratio can be easily obtained.

When the monoazo compound of the present structure obtained is ironized, poor dispersibility in the reaction solvent becomes a problem, and the reaction efficiency of ironization decreases. In order to obtain azo-type iron complex salt with few impurities in high yield, it is important in this invention to disperse | distribute fine enough, adjusting pH with alkali. In this case, it is preferable to use potassium hydroxide.

While adjusting to the desired counter ion, it is necessary to take out azo-type iron complex salt in an acidic state, and to fully wash | clean. For example, washing | cleaning by the water of 60 degreeC which removed the metal is mentioned. The conductivity of the filtrate obtained is preferably 200 µS or less, more preferably 100 µS.

The obtained charge control agent is fine in particle size, flexible, and uniform in shape, and thus can be easily pulverized. Moreover, as needed, grinding | pulverization process and classification process can be performed using grinders, such as a jet mill.

Moreover, it is preferable that specific surface area x is 5 <= <= 15 (m <2> / g), and, as for the azo-type iron complex salt obtained by said method, it is more preferable that it is 5 <= << 10 (m <2> / g). If it is this range, as a result of the charge controllability of a charge control agent being improved, a high resolution image can be obtained by the toner containing it.

Below, the azo-type iron complex salt represented by the said General formula (1) is illustrated concretely.

In general formula (1), substituent R <^1> or R <^3> is a linear or branched C3-C8 alkyl group (for example, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert -Butyl group, n-pentyl group, iso-pentyl group, hexyl group, heptyl group, octyl group and the like are exemplified). Substituents R ^2a , R ^2b , R ^4a or R ^4b are hydrogen atoms, alkyl groups (eg, methyl group, ethyl group, iso-propyl group, n-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group) , Octyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propoxy group, butoxy group, etc. are exemplified), halogen (e.g., F, Cl, Br, I, etc.) Nitro group, carboxyl group.

Preferred embodiments [I] are azo-based iron salts in which the azo-based iron salts of formula (1) are represented by the following formula (2):

[In Formula (2), A ⁺ represents m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ); M, n, and p are m + n + p = 1, 0.7 ≦ m ≦ 1, 0 ≦ n ≦ 0.3, and 0 ≦ p ≦ 0.3.

As a more preferable embodiment [II], the azo iron complex salt of the general formula (1) is an azo iron complex salt represented by the above general formula (2), wherein A ⁺ is m (H ⁺ ) + n ( K ⁺ ), and m and n are numbers of m + n = 1, 0.7 ≦ m ≦ 1, and 0 ≦ n ≦ 0.3.

Furthermore, as a preferable embodiment [III], the azo-type iron complex salt of general formula (1) is an azo-type iron complex salt represented by the said general formula (2) whose average particle diameter is 1-3 micrometers, In formula (2), A ⁺ Represents m (H ⁺ ) + n (K ⁺ ), and m and n are numbers with m + n = 1, 0.9 ≦ m ≦ 0.99, and 0.01 ≦ n ≦ 0.1.

Other specific compounds of the azo iron complex salt represented by the formula (1) are exemplified by the compound represented by the following formula. However, of course, the present invention is not limited to these:

In the formula, the counter ion is hydrogen ion and K ion and Na ion in the mixed cation, the existing ratio is of each 0.7≤m ₁ ≤1, number of 0≤n ₁ ≤0.3, 0≤p ₁ ≤0.3 the channel Is displayed. M ₁ + n ₁ + p ₁ = 1.

[In the formula, the counter ions are mixed cations of hydrogen ion and the K ion, the existing ratio is of each 0.99≤m ₂ ≤1, is shown by the number of 0≤n ₂ ≤0.01. M ₂ + n ₂ = 1.

[Wherein, the counter ion is a mixed cation of hydrogen ion, K ion and Na ion, the abundance of which is 0.9 <m ₃ <1, 0 <n ₃ <0.1, 0 <p ₃ <0.1 It is represented by a number. However, m ₃ + n ₃ + p ₃ = 1.]

[In the formula, the counter ions are mixed cations of hydrogen ion and the K ion, the existing ratio is displayed as a number of from each 0.9≤m _{4 <1, 0 <n 4 ≤0.1} . M ₄ + n ₄ = 1.

[Wherein, the counter ions are mixed cations of hydrogen ions, K ions, and Na ions, and their abundances are 0.75 <m ₅ <1, 0 <n ₅ <0.25, and 0 <p ₅ <0.25, respectively. Is displayed. M ₅ + n ₅ + p ₅ = 1.

[In formula, a counter ion is a mixed cation of hydrogen ion and K ion, The abundance ratio is represented by the number of 0.9 <= m <_6><1, and the number of 0 <n < ₆ ><0.1, respectively. M ₆ + n ₆ = 1.

[In formula, counter ion is hydrogen ion.]

In the formula, the counter ion is hydrogen ion and K ion and Na ion in the mixed cation, the existing ratio is a number of from each 0.99≤m _{7 ≤1, 0≤n 7 ≤0.01, 0≤p} 7 ≤0.01 the channel Is displayed. M ₇ + n ₇ + p ₇ = 1.]

[Wherein, the counter ions are mixed cations of hydrogen ions, K ions and Na ions, the abundances of which are 0.995 ≦ m ₈ ≦ 1, 0 ≦ n ₈ ≦ 0.005, and 0 ≦ p ₈ ≦ 0.005, respectively. Is displayed. M ₈ + n ₈ + p ₈ = 1.

In the formula, the counter ions are mixed cations of hydrogen ion and the K ion and Na ion, and the existing ratio is of each 0.997≤m ₉ ≤1, number of 0≤n ₉ ≤0.003, number of 0≤p ₉ ≤0.003 Indicates. M ₉ + n ₉ + p ₉ = 1.

[In the formula, the counter ions are mixed cations of hydrogen ion and the K ion, the existing ratio is of each 0.7≤m ₁₀ <1, is shown by the number of 0 <n ₁₀ ≤0.3. M ₁₀ + n ₁₀ = 1.

In the formula, the counter ions are mixed cations of hydrogen ion and the K ion and Na ion, and the abundance ratio is ₁₁ in each 0.8≤m ≤0.998, number of 0.01≤n ₁₁ ≤0.2, number of 0≤p ₁₁ ≤0.01 Indicates. M ₁₁ + n ₁₁ + p ₁₁ = 1.

In the formula, the counter ions are mixed cations of hydrogen ion and the K ion and Na ion, and the existence ratio is, respectively 0.8≤m ₁₂ ≤1.0, 0≤n number of from ₁₂ ≤0.2, 0≤p ₁₂ ≤0.2 of Indicates a number. However, m ₁₂ + n ₁₂ + p ₁₂ = 1.]

In the formula, the counter ions are mixed cations of hydrogen ion and the K ion and Na ion, and the existing ratio is of each 0.75≤m ₁₃ ≤1.0, 0≤n ₁₃ ≤0.25 number of, 0≤p number of from ₁₃ ≤0.25 Indicates. M ₁₃ + n ₁₃ + p ₁₃ = 1.

In the formula, the counter ions are mixed cations of hydrogen ion and the K ion and Na ion, and the abundance ratio is ₁₄ in each 0.7≤m ≤1, 0≤n number of from ₁₄ ≤0.3, 0≤p number of from ₁₄ ≤0.3 Indicates. M ₁₄ + n ₁₄ + p ₁₄ = 1.

In the formula, the counter ions are mixed cations of hydrogen ion and the K ion and Na ion, and the abundance ratio is ₁₅ in each 0.75≤m ≤1, number of 0≤n ₁₅ ≤0.25, 0≤p number of from ₁₅ ≤0.25 Indicates. M ₁₅ + n ₁₅ + p ₁₅ = 1.

[In the formula, the counter ions are mixed cations of hydrogen ion and the K ion, the abundance ratio may each 0.995≤m ₁₆ ≤1, 0≤n ₁₆ ≤0.005 which is shown by the number. M ₁₆ + n ₁₆ = 1.

[In the formula, the counter ions are mixed cations of hydrogen ion and the K ion, the abundance ratio is ₁₇ in each 0.8≤m ≤1, it is shown by the number of 0≤n ₁₇ ≤0.2. M ₁₇ + n ₁₇ = 1.

[In the formula, the counter ions are mixed cations of hydrogen ion and the K ion, the existing ratio is of each 0.7≤m ₁₈ ≤1, 0≤n ₁₈ ≤0.3 which is shown by the number. M ₁₈ + n ₁₈ = 1.

The electrostatic charge image developing toner of the present invention contains a charge control agent containing an azo-based iron salt represented by the formula (1). More specifically, the toner contains, for example, 0.1 to 10 parts by weight of the charge control agent and 0.5 to 10 parts by weight of the colorant based on 100 parts by weight of the resin for toner.

The electrostatic charge image developing toner prepared by using the charge control agent has a rapid rise in charging even at a low speed or a high speed when developing an electrostatic latent image, and enables a sufficient charge amount to be charged, so that charging can be stably maintained.

The electrostatic charge image developing toner prepared using the charge control agent has a ratio of the ratio of charge control agent from toner particles, i.e., a particle analyzer analysis, in order to maintain good properties of the charge control agent. It is preferable that the free ratio of metal Fe is 0.01 to 3%. As a result, in order for the charge control agent to be surely present on the surface of the toner particles, the toner charging property becomes uniform, and the rise of the triboelectric charge of the toner becomes good.

On the other hand, the toner with a significant release and release of the charge control agent from the toner particles is charged up, and after several sheets of output, the resultant after the glass and detached charge control agent adheres to the carrier surface or is further fixed. As a result, the charging imparting ability of the carrier is remarkably lowered, which causes cloudiness and scattering of the toner.

The glass ratio of this charge control agent can be obtained by measuring the number fractional ratio of Fe with a commercially available particle analyzer DP-1000 (brand name of Horiba Corporation make), for example. Toner analysis in the particle analyzer is described in the Japanese Hardcopy 97 Paper, pages 65-68.

This charge control agent, which has a specific volume resistivity and a particle size, has excellent environmental stability. The toner for electrostatic image development containing the same has a low charge reduction rate of 0.1 to 10% in the evaluation of environmental stability under high temperature and high humidity, and thus can minimize the occurrence of fluctuations in image density, blur, and toner scattering due to the toner. have.

The image copied by rubbing this toner and charging negatively is clear and of high quality. This toner has a high rate of charging, so that not only high-speed copying but also low-speed copying at a maximum circumferential speed of 600 cm / min or less can form a clear electrostatic latent image, thereby forming a high-resolution clear image and excellent copying characteristics. Do.

This electrostatic charge image developing toner is produced, for example, as follows. That is, the binder resin and colorant for toner, and the charge control agent and, if necessary, additives such as a magnetic material or a fluidizing agent are sufficiently mixed by a mixer such as a ball mill, and then, using a heat mixer such as a heating roll or a kneader. Toner having an average particle diameter of 5 to 20 µm is obtained by melt kneading, cooling and solidifying, followed by grinding and classifying.

In addition, a method of obtaining by dispersing a material in a binder resin solution, followed by spray drying, a method of preparing a toner by mixing a predetermined material with an monomer to constitute the binder resin to form an emulsion suspension and then polymerizing to obtain a toner (for example, The toner for developing electrostatic images can also be obtained by the methods described in JP-A-2-260461 and JP-A2-32365.

This electrostatic charge image developing toner can be used as a two-component developer. In that case, this toner and carrier powder are mixed to prepare a developer. This developer is used when developing by, for example, a two-component magnetic brush developing method.

As a carrier powder, all well-known thing can be used, It does not specifically limit. Specifically, iron powders, nickel powders, ferrite powders, glass beads, or the like having a particle diameter of about 50 to 200 µm may be used, and the surfaces thereof may be acrylic acid ester copolymers, styrene-acrylic acid ester copolymers, silicone resins, It may be coated with polyamide resin, fluorinated ethylene resin or the like.

This electrostatic charge image developing toner can also be used as a one-component developer. In that case, when producing the toner as described above, fine powder made of ferromagnetic material such as iron powder, nickel powder, ferrite powder or the like is added and dispersed to prepare a developer. This developer is used when developing by the contact developing method, the jumping developing method, etc., for example.

As the binder resin for toners contained in the electrostatic charge image developing toner, a known synthetic resin or natural resin can be used. The binder resin is, for example, a homopolymer of styrene and its substituents such as polystyrene, poly-p-chlorostyrene, and polyvinyl toluene; Styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α- Methyl chloromethacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene Styrene-based copolymers such as copolymers, styrene-isoprene copolymers and styrene-acrylonitrile-indene copolymers. Examples of comonomers for the styrene monomers of such styrene copolymers include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, -2-ethylhexyl acrylate, phenyl methacrylate, methacrylic acid, and meta. Monocarboxylic acids having a double bond such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, acrylamide and substituents thereof; Dicarboxylic acids having a double bond such as maleic acid, butyl maleate, methyl maleate and dimethyl maleate, and substituents thereof; Vinyl esters such as vinyl chloride, vinyl acetate and vinyl benzoate; Ethylene olefins such as ethylene, propylene and butylene; Vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone; And vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether. These may be used alone or in combination of two or more thereof.

The binder resin may be a styrene resin crosslinked with a crosslinking agent. As a crosslinking agent, the compound which mainly has 2 or more polymerizable double bond can be used, Aromatic divinyl compounds, such as divinylbenzene and divinyl naphthalene; Carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol methacrylate and 1,3-butanediol dimethacrylate; Divinyl compounds of divinyl aniline, divinyl ether, divinyl sulfide and divinyl sulfone; The compound which has three or more vinyl groups is mentioned. These may be used alone or in combination of two or more thereof.

The binder resin is polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane resin, xylene resin, polyamide The resin, furan resin, epoxy resin, polyvinyl butyral, terpene resin, coumarone-indene resin and petroleum resin may be used.

The toner for electrostatic charge image development may contain a well-known dye and pigment as a coloring agent. As the colorant, for example, carbon black (for example, acetylene black, lamp black, thermal black, crucible black, channel black, ketene black, etc., titanium black, black iron oxide, etc.) Can be mentioned.

The electrostatic charge image developing toner may further contain a release agent. Release agents include paraffins having 8 or more carbon atoms as exemplified by paraffin wax, paraffin latex, microcrystalline wax; Polyolefins exemplified by polypropylene and polyethylene wax are preferred. These mold release agents can be used individually or in mixture of two or more. The addition amount is preferably in the range of 0.3 to 10% by weight. When the amount of the release agent is less than 0.3% by weight, the mold release agent does not sufficiently function as the release agent when the image is fixed. If the content exceeds 10% by weight, the release agent on the surface of the toner increases, resulting in poor charging, scattering of the toner from the developer carrier or deteriorating image quality, adhesion between the toner particles, the layering member or the developer. Since the interaction with the carrier becomes large, the cleaning property is reduced.

The wax is more preferable in the case of a wax having an average molecular weight of 3000 to 10000, since the offset property of the toner, which functions well as a release agent, is further improved.

The electrostatic charge image developing toner may contain a magnetic toner containing a magnetic material. Magnetic materials include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese and zinc. It is preferable that these magnetic materials are magnetic components whose BET (Brunauer-Emmett-Teller) specific surface area is 1-20 m <2> / g by the nitrogen adsorption method, and Mohs' hardness is 5-7. Examples of the shape of the magnetic material include an octahedron, a hexahedron, a spherical shape, a needle shape, a scale shape, and the like, but one having less anisotropy such as an octahedron, a hexahedron, a spherical shape, or the like is preferable. What has an isotropic shape can achieve favorable dispersion also about binder resin and wax in toner. It is preferable that the average particle diameter of the said magnetic material is 0.05-1.0 micrometer.

It is preferable that 50-200 weight part contains this magnetic material with respect to 100 weight part of binder resin for toner, and it is more preferable if it contains 70-150 weight part. If it is less than 50 parts by weight, the conveyability of the toner is insufficient, and staining occurs on the developer layer on the developer carrier, which tends to become an image spot, and a decrease in image density due to excessive increase in charging of the developer tends to occur. On the other hand, if it exceeds 200 parts by weight, charging of the developer cannot be sufficiently obtained, so that image concentration decreases easily.

The toner for electrostatic charge image development may contain an inorganic fine powder or a hydrophobic inorganic fine powder because of improvements in environmental stability, charging stability, developability, fluidity, and storage properties. Examples of such powders include fine silica powders, fine titanium oxide powders and hydrophobic compounds thereof. You may use this powder individually or in mixture of two or more.

Silica fine powder includes dry silica produced from silicon halide by vapor phase oxidation called dry method; Dry silica, also called fumed silica; Dry silica in which a composite fine powder of silica and another metal oxide is produced from a metal halide compound such as aluminum chloride or titanium chloride and a silicon halide by a dry method; So-called wet silica made of water glass or the like can be used. In particular, the surface and less silanol groups inside, and Na ^₂ O, SO _{3 2} ^- is preferably less production residue such as fumed silica.

It is preferable that the silica fine powder is hydrophobized. The hydrophobization treatment is a treatment with an organosilicon compound that reacts or physically adsorbs with the silica fine powder, and preferably, after treating the dry fine powder produced by vapor phase oxidation of the silicon halide compound with a silane coupling agent or with a silane coupling agent. It is a method of treating with an organic silicon compound such as silicone oil while treating with a coupling agent.

As the silane coupling agent used for the hydrophobization treatment, for example, hexamethylenedisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, aryldimethylchlorosilane , Arylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilyl mercaptan , Trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethyldiethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3 Located at the terminal with divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane and 2 to 12 siloxane units per molecule The dimethyl polysiloxane containing the hydroxyl group couple | bonded with one silicon atom in each unit is mentioned.

Silicone oil is mentioned as an organosilicon compound. Preferred silicone oils include dimethylsilicone oil, methylphenylsilicone oil, α-methylstyrene modified silicone oil, chlorophenylsilicone oil and fluorine-modified silicone oil.

The electrostatic charge image developing toner may contain an external additive as necessary. Examples of the external additives include resin fine particles and inorganic fine particles that function as charging aids, conductivity giving agents, fluidity giving agents, anti-caulking agents, mold release agents during thermal roller fixing, lubricants, abrasives, and developability improvers.

Titanium oxide and aluminum oxide are mentioned as a fluidity imparting agent, Especially, a hydrophobic thing is preferable.

Examples of the lubricant include polytetrafluoroethylene, zinc stearate, and polyvinylidene fluoride. Moreover, as an abrasive, cerium oxide, silicon carbide, strontium titanate is mentioned, for example.

Examples of the conductivity providing agent include carbon black, zinc oxide, antimony oxide, and tin oxide.

As a developability improving agent, a small amount of reverse polarity white fine particles and black fine particles can be used.

Next, the image forming method of the present invention will be described in detail.

The image forming method includes a latent image forming step of forming a latent image on a latent image retainer, a developing step of developing a latent image by using a developer layered on a developer carrier on the latent image retainer to form a toner image, and the toner image Is carried out in the order of a transfer step of transferring the transfer onto the transfer member, followed by a cleaning step and a fixing step of passionately fixing the toner image on the transfer member.

The latent image forming step is to form an electrostatic latent image on a latent image holder made of a cylindrical frame supporting the photosensitive layer or dielectric layer and the like by a known method, for example, electrophotographic method or electrostatic locking method. The photosensitive layer is formed of a material such as an organic compound or amorphous silicon. As a cylindrical base body which supports this photosensitive layer, what was obtained by surface-processing after extrusion molding aluminum or an aluminum alloy is used.

In the developing step, a thin layer is formed of a developer by a layer forming blade such as an elastic blade on the developer carrying member, which is a developing roll having a cylindrical shape, and conveyed to a developing unit. When a bias voltage is applied in between, the electrostatic latent image is developed by the developer, thereby forming a toner image. At the time of development, the latent image retainer holding the developing roll and the electrostatic latent image is contacted at the developing portion or provided at regular intervals.

The one-component developer carrier, which is an example of the developer carrier, has a surface of the substrate in order to control the transportability or chargeability of the toner and the sleeve drawn from a metal or ceramics such as an elastic sleeve such as silicone rubber or aluminum or stainless steel (SUS). Sleeves subjected to surface treatment such as oxidation or polishing, blasting treatment or coating with resin are used. Formation of the toner layer on the developing roll is performed by bringing the layer forming blade into contact with the sleeve surface. When the layered blade is an elastic blade, the material is preferably a rubber elastic body such as silicone rubber or urethane rubber, and may be an elastic body to which organic or inorganic substances are added and dispersed in order to control the amount of toner charging.

The two-component developer carrier, which is another example of the developer carrier, has a surface such as oxidation, polishing, and blasting on the surface of the substrate in order to control the transportability or chargeability of the sleeve made of metal such as aluminum, SUS, and brass and the developer. The treated sleeve is used. Developer formation on the developing roller is performed by slightly detaching the layered blade from the sleeve surface.

The transfer step transfers the toner image on the latent image retainer onto paper which is a transfer body. The transfer means may be, for example, a contact type means for pressing the roll transfer machine to the latent image bearing, or a non-contact means employing a corotron. However, the contact type means is preferable because it is performed by a compact apparatus. .

The cleaning step is to remove toner remaining in the transfer step without being transferred by the cleaner. The means for cleaning may be a means using a cleaning blade or a cleaning roll. The cleaning blade is made of an elastic rubber such as silicone rubber or urethane rubber.

The fixing step is to fix the toner image transferred to the transfer member with the fixing unit. The means for fixing is preferably a passion fixing method using a heat roll, but may be a pressure fixing method.

Next, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to these, of course.

EMBODIMENT OF THE INVENTION Hereafter, the Example of the charge control agent of this invention and the toner for developing the charge-charge image containing it are demonstrated in detail.

Charge control agents A to F of the present invention consisting of the azo iron complex salt of the formula (1) and charge control agents G to H outside the scope of the present invention were prepared, and physical and chemical analysis and physical property evaluation were performed.

pharmacy Example  One: Charge control agent  A

(1.1 Preparation of Charge Control Agent A)

Charge control agent A was prepared as follows.

(1) Synthesis of Monoazo Dye

5821.0 g of 4-tert-butyl-2-aminophenol and 1095.62 g of concentrated hydrochloric acid were added to 2525 L of water, and then 628.7 g of 36% aqueous sodium nitrite solution was slowly added while cooling with water from the outside of the reaction system. Diazolation was performed to obtain a diazonium salt. The above diazonium salt solution and 616.4 g of butanol were added dropwise to an aqueous solution in which 805.7 g of naphthol AS and 964.9 g of an aqueous 48.5% potassium hydroxide solution were dissolved in 4 L of water, followed by reacting for 2 hours. Thereafter, the precipitated monoazo compound was filtered and washed with water to obtain 3511 g of a wet cake having a water content of 63.2%.

(2) Synthesis of Azo Ferric Salt and Preparation of Charge Control Agent

10 g of the wet cake of the obtained monoazo compound was dried, and Na and K contents were measured by atomic absorption. The Na content was 0.01% and the K content was 0.04%. The amount of residual water in the dye was subtracted from the solid content of the wet cake, and 275.9 g of a 48.5% potassium hydroxide aqueous solution was added to a butanol-water (370 g: 6740 g) mixed liquid in which 2000 g of the wet cake of this monoazo compound was dispersed. It heated to 90 degreeC, and stirred and dispersed for 1 hour. Subsequently, 402.0 g of 41% ferric sulfate aqueous solution (a ferric sulfate aqueous solution having a Mn concentration of 1300 ppm) was added dropwise. PH of the reaction liquid at this time was 3.1. Then, it heated to 94 degreeC, heated to reflux for 5 hours, and synthesize | combined an azo-type iron complex salt. The precipitated azo iron salt was filtered, and the conductivity of the filtrate washed with 30 kg of ion-exchanged water at 60 ° C was 85 µS. The cake obtained was dried to obtain 752.9 g of the desired charge control agent A made of the azo iron complex salt represented by the following general formula (3).

(1.2 Analysis and evaluation of charge control agent A)

About this charge control agent A, the following physical analysis and physical property evaluation were performed.

(Measurement 1) Measurement of Average Particle Diameter

About 10 mg of the charge control agent which is agglomerated particle was added to the solution of 10 v / v% of activator dry wells (brand name of Fuji Photograph Co., Ltd. product), it was made into the liquid mixture, and ultrasonic vibration was carried out for 10 minutes. 0.1 ml of this mixed solution was added to about 260 ml of the dispersion water in the particle size distribution analyzer LA-910 (trade name, manufactured by Horiba Co., Ltd.), and ultrasonic vibration was further performed for 1 minute to finely disperse the particle size distribution. The average particle diameter of the charge control agent A was 2.5 micrometers.

(Measurement 2) Measurement of the volume specific resistance

The volume specific resistivity of the charge control agent A which is a measurement sample was measured using the apparatus shown in FIG.

The measurement sample 6 is filled into a ring 3 made of polytetrafluoroethylene, and the lower electrode 1 and the upper electrode 2 are disposed to contact the measurement sample 6, and the upper electrode It was calculated by applying a voltage between both electrodes while applying a load to (2), and measuring the current flowing at that time by the ammeter 5. The measurement environment had a temperature of 23 ± 2 ° C. and a humidity of 50 ± 5% RH, the load of the upper electrode 2 was 2000 kg, and the applied direct current voltage was 500 V. The volume specific resistivity of the charge control agent A was 0.92 × 10 ¹⁵ Ω · cm. For reference, in Fig. 1, reference numeral 4 denotes an insulating plate, and reference numeral d denotes a measurement sample thickness.

(Measurement 3) Differential Thermal Gravimetric Measurement

It heated to 550 degreeC using TG / DTA6200 (brand name of NS Eye Nano Technology Co., Ltd.), and thermogravimetric measurement was performed. The weight loss of the charge control agent was 92.3%.

(Measurement 4)

(1) Analysis of counter ions

Measurement of the amount of hydrogen ions, the amount of Na ions and the amount of K ions

(2) Metal analysis of iron sulfate and impurities (metal salts, metal oxides)

Measurement of Mn Amount

As a result of measuring the Na and K content in the charge control agent using the atomic absorption spectrometer SpectrAA-220FS (trade name of Varian Technologies Japan Limited), the molar percentage present as a counter ion was 99.7% of hydrogen ions. The amount of Na ions was 0% and the amount of K ions was 0.3%. In addition, the amount of Mn which is an impurity was 50 ppm or less.

(Measurement 5) Measurement of specific surface area

The sample was subjected to vacuum degassing at room temperature, and the specific surface area (BET) of the charge control agent was measured using a specific surface area measuring device, Autosorb 3 (trade name of QUANTACHROME Co.). As a result, the specific surface area of the charge control agent was 9.3 m 2 / g.

pharmacy Example  2: Charge control agent  B

Except for changing butanol-water to 296 g: 5329 g in Preparation Example 1, the preparation was carried out in the same manner as in Preparation Example 1, and was made of the azo-based iron salt represented by the formula (3); And p obtained a charge control agent B different from that of Preparation Example 1. The charge control agent B was subjected to physicochemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 1. In addition, the same results as in Example 1 were obtained in the metal analysis of impurities.

Charge control agent number Charge control agent A Charge control agent B Ratio of m, n and p in counter ions m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ) m 0.997 0.993 n 0.003 0.007 p 0 0 Average particle size (㎛) 2.5 3.8 Volume specific resistance (× 10 ¹⁵ Ωcm) 0.9 2.3 Weight loss rate (%) 92.3 92.5 Specific surface area (㎡ / g) 9.3 6.1

pharmacy Example  3: Charge control agent  C

Except for changing butanol-water to 333 g: 6066 g in Preparation Example 1, the same procedure as in Preparation Example 1 was carried out to form an azo-based iron complex represented by the formula (3), and the proportion of the counter ion m, Charge control agent C different from n and p of the preparation example 1 was obtained. The charge control agent C was subjected to physical and chemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 2. In addition, the same results as in Example 1 were obtained in the metal analysis of impurities.

pharmacy Example  4: Charge control agent  D

Except for changing the 48.5% potassium hydroxide aqueous solution to 260g of 20% sodium hydroxide aqueous solution in the above-mentioned preparation example 1, it was made of the azo-based iron complex salt represented by the said Formula (3) similarly to preparation example 1, and the counter ion Charge m, n, and p which were different from the thing of Preparation Example 1 were obtained. The charge control agent D was subjected to physicochemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 2. In addition, the same results as in Example 1 were obtained in the metal analysis of impurities.

Charge control agent number Charge control agent C Charge control agent D Ratio of m, n and p in counter ions m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ) m 0.995 1.0 n 0.005 0 p 0 0 Average particle size (㎛) 2.4 3.9 Volume specific resistance (× 10 ¹⁵ Ωcm) 0.7 3.6 Weight loss rate (%) 92.2 91.3

pharmacy Example  5: Charge control agent  E

In Preparation Example 1, except that 4-tert-butyl-2-aminophenol of 1.1 (1) was changed to 4-n-pentyl-2-aminophenol and 48.5% potassium hydroxide solution amount was changed to 353 g. It carried out similarly to the preparation example 1, Comprising the azo-type iron complex salt represented by following formula (4), The ratio m, n, and p of the counter ion obtained the charge control agent E different from the preparation example 1. The charge control agent E was subjected to physical and chemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 3.

pharmacy Example  6: Charge control agent  F

Except for changing the amount of 48.5% potassium hydroxide aqueous solution to 303.5g in the said preparation example 1, it consists of azo-type iron complex salt represented by the said Formula (3) similarly to preparation example 1, and the ratio m of the counter ion, Charge control agent F different from n and p of the preparation example 1 was obtained. The charge control agent F was subjected to physicochemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 3.

Charge control agent number Charge control agent E Charge control agent F Ratio of m, n and p in counter ions m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ) m 0.85 0.79 n 0.13 0.15 p 0.02 0.06 Average particle size (㎛) 3.9 3.4 Volume specific resistance (× 10 ¹⁵ Ωcm) 1.4 0.8

Comparison Example  One: Charge control agent  G

Except for changing the butanol-water to 5000 g of butanol in Preparation Example 1, the preparation was carried out in the same manner as in Preparation Example 1, and was made of the azo iron complex salt represented by the formula (3); And a charge control agent G whose p is outside the application range of this invention different from the preparation example 1 was obtained. The charge control agent G was subjected to physicochemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 4.

Comparison Example  2: Charge control agent  H

In Preparation Example 1, except that 4-tert-butyl-2-aminophenol of 1.1 (1) was changed to 4-methyl-2-aminophenol and 48.5% potassium hydroxide solution amount was changed to 250 g. In the same manner as in Example 1, the charge control agent H composed of the azo iron complex salt represented by the chemical formula (5), wherein the ratios m, n and p of the counter ions are outside the application range of the present invention other than that of Preparation Example 1 Got. The charge control agent H was subjected to physical and chemical analysis and physical property evaluation in the same manner as in Preparation Example 1. The results are summarized in Table 4.

Charge control agent number Charge control agent G Charge control agent H Ratio of m, n and p in counter ions m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ) m 1.0 0.998 n 0 0.002 p 0 0 Average particle size (㎛) 4.9 3.0 Volume specific resistance (× 10 ¹⁵ Ωcm) 5.1 0.8 Weight loss rate (%) 91.6 84.2

In addition, the physical and chemical properties and physical property evaluation of the charge control agent T-77 (trade name of Hodogaya Chemical Co., Ltd. product) represented by the following general formula (6) were performed in the same manner as in Preparation Example 1 for comparison. . The results are summarized in Table 5.

In the formula, the counter ion b ⁺ is mixed cations of the ammonium ion (NH ₄ ⁺⁾ and Na ions and hydrogen ions, it is estimated to be greater than or equal to NH ⁺ ₄ is 95%.]

Charge control agent number T-77 Counter Ion of Azo Ferric Salts More than 95% NH ₄ ⁺ Average particle size (㎛) 3.0 Volume specific resistance (× 10 ¹⁵ Ωcm) 0.1 Weight loss rate (%) 91.7

Next, the charge control agents A to F are used to prepare the electrostatic charge image developing toners to which the present invention is applied, respectively, and the charge control agents G to H and the charge control agent T-77 are used to apply the present invention. Toner for electrostatic charge image development was prepared. These toners were subjected to frictional charge measurement and charge amount environmental stability evaluation.

Example  One

100 parts by weight of styrene-acrylic copolymer resin (CPR-600B: trade name of Mitsui Chemical Co., Ltd.), 2 parts by weight of low molecular weight polypropylene (Biscol 550-P: trade name of Sanyo Chemical Industries, Ltd.) 6 parts by weight of carbon black (MA100: Mitsubishi Chemical Corporation) and 1 part by weight of charge control agent A were uniformly premixed with a high speed mixer. Subsequently, the mixture was melt kneaded (temperature 130 ° C.) in a Kneader-S1KRC2 axial mixing extruder (trade name of Kurimoto Steel Co., Ltd.), and after cooling, coarsely pulverized in a rotor mill ZM1 (trade name of Retsch Corporation). The obtained crude powder was ground finely using an air jet mill CO-JET System α (trade name of Seishin Corporation) with a classifier to obtain a toner having a particle size of 10 µm.

To 50 parts by weight of the obtained toner, 50 parts by weight of an iron carrier (F-150: trade name of Powder Tech Co., Ltd.) was mixed to adjust the developer.

(Measurement 6) Measurement of Friction Charge

To 2.5 parts by weight of the obtained toner, 50 parts by weight of an iron carrier (F-150: Powderatech Co., Ltd. product) was weighed into a poly bottle, charged with a ball mill at a rotational speed of 100 rpm, and charged to a developer. The amount of charge over time was measured under the conditions (20 ° C, 60% relative humidity). Table 6 shows the measurement results of the amount of frictional charge for each stirring time (minutes).

(Measurement 7) Measurement of environmental stability of charge quantity

Initially blow-off charging under the conditions of low temperature low humidity (5 ° C, 30% relative humidity), normal temperature humidity (25 ° C, 50% relative humidity) and high temperature high humidity (35 ° C, 90% relative humidity). Table 7 shows the results of measuring the amount, that is, the measurement result of the electric charge environmental stability. In addition, the rate of decrease of charge represents the rate of decrease of the amount of initial blowoff charge at this high temperature and high humidity relative to the amount of initial blowoff charge at this room temperature and humidity.

Example  2 to 6

The toners of Examples 2 to 6 were prepared in the same manner as in Example 1, except that the charge control agent A used in Example 1 was changed to the charge control agents B to F. In addition, the results of frictional charge and charge amount environmental stability measured in the same manner as in Example 1 are shown in Tables 6 and 7.

Comparative example  1 to 2

The toners of Comparative Examples 1 and 2 were produced in the same manner as in Example 1, except that the charge control agent A used in Example 1 was changed to the charge control agents G to H. In addition, the results of frictional charge and charge amount environmental stability measured in the same manner as in Example 1 are shown in Tables 6 and 7.

Comparative example  3

The toner of Comparative Example 3 was prepared in the same manner as in Example 1 except that the charge control agent A used in Example 1 was changed to the charge control agent T-77. In addition, the results of frictional charge amount and charge amount environmental stability measured in the same manner as in Example 1 are shown in Tables 6 and 7.

As apparent from Table 6, the toner of Comparative Example 1 had an excessively large average particle diameter of the charge control agent made of an azo-based iron salt, resulting in poor dispersion of the charge control agent into the toner, resulting in inferior synergistic properties. On the other hand, the toner of the example had an appropriate volume specific resistance value and average particle diameter of the charge control agent made of azo-based iron salt, resulting in excellent rise and sufficient saturated charge amount.

In addition, as is apparent from Tables 6 and 7, the toner of Comparative Example 2 had a short alkyl group in the azo-based iron salt of the charge control agent made of azo-based iron salt, and the hydrophobicity did not improve, so that the amount of saturated charge was low and the environment Lack of stability In contrast, the toner of this embodiment is excellent in charging stability and small in charge amount fluctuation under various environments.

Further, the toner has a low saturated charge amount when the volume specific resistance of the charge control agent made of azo-based iron salt is low, and lacks stability when the volume specific resistance is large.

Next, the ratio of liberation of the central metal Fe in the formula (1) from the toner was measured.

(Measurement 8) Determination of the Free Rate of Azo Ferric Salt from Toner Particles

The glass of azo iron complex salt was classified by measuring the center metal Fe.

About the toner prepared in Examples 1, 4 and Comparative Example 3, the ratio of Fe was measured using a particle analyzer DP-1000 (trade name, manufactured by Horiba Co., Ltd.), and a synchronous distribution chart was created. The results are shown in Table 8 and FIGS. 2 to 4.

Further, the C-Fe dispersion width in Table 8 is a plot from the slope of the trigonometric voltage corresponding to the particle size size of Fe with respect to the trigeminal voltage corresponding to the particle size size of the toner indicated as the base material C in FIGS. Is the dispersion width of The narrower the dispersion width, the more uniformly the Fe adheres to the toner, indicating that there is no variation in the Fe concentration. The dispersion width of the comparative example 3 was made into the standard, and the magnitude with it is shown.

In the synchronous distribution diagram, when a mixed powder composed of a plurality of single substances enters the plasma, a luminescence signal corresponding to each single substance is observed with a time difference, but when a weld body composed of a plurality of single substances enters the plasma, The emission signal is measured and created by using the observation of the emission signal in synchronization. The Fe glass ratio is calculated as the Fe single light emission rate, and is the ratio of Fe which does not emit light simultaneously with the base material C, i.e., the toner, and represents the proportion of Fe particles not attached to the toner.

toner C-Fe dispersion width Fe glass ratio Example 1 0.172 littleness 1.88 Example 4 0.227 littleness 1.85 Comparative Example 3 0.252 Standard 3.43

As is apparent from Table 8 and Figs. 2 to 4, the toner of the examples had an Fe glass ratio of 3% or less. When the ratio of the charge control agent is 0.01 to 3.00% in this manner, since the charge control agent is reliably present on the surface of the toner particles, the toner charging property becomes uniform, and the increase in the triboelectric charge of the toner becomes good. In addition, when the iron glass ratio of the charge control agent is large, the amount of charge control agent released from the surface layer of the toner particles is significantly increased. Therefore, the charge control agent attached to and adhered to the surface of the carrier is attached and adhered to the carrier to significantly increase the charge applying ability. Lowers.

The charge control agent used in the electrostatic charge image developing toner of the present invention is excellent in negatively charged women and stability thereof, and has good dispersibility in resin for toner. The electrostatic charge image developing toner of the present invention containing this charge control agent has a rapid rise, excellent stability over time of charging, and excellent storage stability and durability. In particular, since there are few impurities, safety is high and environmental stability is excellent.

According to the image forming method of the present invention using this toner, fixability and non-offsetability in a wide range of temperatures can be realized, and stable copy images can be formed.

In addition, the charge control agent of the present invention can be used to charge toner or powder coating. The toner containing this can be used when printing or copying by an image forming method such as an electrophotographic method.

Claims (12)

The charge control agent containing the azo-type iron complex salt represented by following General formula (1), whose average particle diameter is 1-4 micrometers, and whose volume specific resistivity is 0.2 * 10 <^15> -7 * 10 <^15> ohm * cm. ; And A toner for electrostatic image development comprising a binder resin for toner:

In the formula (1), R ¹ and R ³ are the same as or different from each other, and are a linear or branched alkyl group having 3 to 8 carbon atoms; R ^2a , R ^2b , R ^4a and R ^4b are the same or different from each other and are selected from the group consisting of a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a nitro group and a carboxyl group; A ⁺ represents m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ), wherein m, n and p are m + n + p = 1, 0.7 ≦ m ≦ 1, 0 ≦ n ≦ 0.3 And 0 ≦ p ≦ 0.3. The toner for electrostatic image development according to claim 1, wherein the weight reduction rate of the azo-based iron salt by differential thermal thermogravimetric analysis is 90% or more. The toner for electrostatic image development according to claim 1, further comprising a wax. 2. The electrostatic charge image according to claim 1, wherein the ratio of free ratio obtained from the toner of the azo-based iron salt is in the range of 0.01 to 3%. Developing toner. The toner for electrostatic image development according to claim 1, wherein the reduction rate of charge amount at high temperature of 35 ° C and high humidity of 90% relative to the charge amount at 25 ° C and 50% relative humidity is 0.1 to 10%. . 2. The toner for electrostatic image development according to claim 1, comprising 0.1 to 10 parts by weight of said charge control agent and 100 parts by weight of said toner binder resin. On the developer carrier disposed to face the electrostatic latent image bearing at intervals, it is represented by the following general formula (1), and its average particle diameter is 1 to 4 m, and its volume specific resistivity is 0.2x10 ¹⁵ to 7x. Adsorbing a developer including a charge control agent containing an azo iron complex salt of 10 ¹⁵ Ω · cm and a toner for electrostatic image development containing a binder resin for a toner to form a toner layer; And Adsorbing the toner in the toner layer to the electrostatic latent image bearing member to develop the electrostatic latent image thereof;

In the formula (1), R ¹ and R ³ are the same as or different from each other, and are a linear or branched alkyl group having 3 to 8 carbon atoms; R ^2a , R ^2b , R ^4a and R ^4b are the same or different from each other and are selected from the group consisting of a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a nitro group and a carboxyl group; A ⁺ represents m (H ⁺ ) + n (K ⁺ ) + p (Na ⁺ ), wherein m, n and p are m + n + p = 1, 0.7 ≦ m ≦ 1, 0 ≦ n ≦ 0.3 And 0 ≦ p ≦ 0.3. 8. The image forming method according to claim 7, wherein the weight loss rate of the azo-based iron salt by differential thermal thermogravimetric analysis is 90% or more. 8. The image forming method according to claim 7, wherein the electrostatic charge image developing toner further contains wax. 8. The image forming process according to claim 7, wherein the ratio of the ratio of the free metal obtained from the toner of the azo-based iron salt to be measured is 0.01 to 3%. Way. 8. The image forming method according to claim 7, wherein a reduction rate of the charge amount at a high temperature of 35 ° C and a high humidity of 90% relative to the charge amount at 25 ° C and a relative humidity of 50% is 0.1 to 10%. 8. The image forming method according to claim 7, wherein 0.1 to 10 parts by weight of the charge control agent and 100 parts by weight of the toner binder resin are contained in the electrostatic charge image developing toner.

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